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https://issues.apache.org/jira/browse/LUCENE-8581?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16708888#comment-16708888
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Ignacio Vera commented on LUCENE-8581:
--------------------------------------

 
{quote}it seems that giving all triangles the same orientation and rotating 
vertices would help reduce the number of conditionals?
{quote}
Yes, with this strategy you reduce the possible combinations to 2^3.
{quote}is the reason why we think we should preserve ordering that we expect it 
to be easier later to record which edges of the triangles are shared with the 
polygon?
{quote}
I don't think it will matter, you should still be able to recognise each edge 
and mark it accordingly.
{quote}maybe we should just have 2^3 constants instead  of FIRST_BIT | 
SECOND_BIT | THIRD_BIT?
{quote}
That should make the code more readable.

> Change LatLonShape encoding to use 4 BYTES Per Dimension
> --------------------------------------------------------
>
>                 Key: LUCENE-8581
>                 URL: https://issues.apache.org/jira/browse/LUCENE-8581
>             Project: Lucene - Core
>          Issue Type: New Feature
>            Reporter: Nicholas Knize
>            Assignee: Ignacio Vera
>            Priority: Major
>         Attachments: LUCENE-8581.patch, LUCENE-8581.patch
>
>
> {{LatLonShape}} tessellated triangles currently use a relatively naive 
> encoding with the first four dimensions as the bounding box of the triangle 
> and the last three dimensions as the vertices of the triangle. To encode the 
> {{x,y}} vertices in the last three dimensions requires {{bytesPerDim}} to be 
> set to 8, with 4 bytes for the x & y axis, respectively. We can reduce 
> {{bytesPerDim}} to 4 by encoding the index(es) of the vertices shared by the 
> bounding box along with the orientation of the triangle. This also opens the 
> door for supporting {{CONTAINS}} queries.



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